The control of bleeding is essential in surgical procedures to improve the outcomes and to shorten the duration of the surgery in the operating room. Several hemostatic materials including oxidized cellulosic based material has been used as a dressing in a variety of surgical procedures, including neurosurgery, abdominal surgery, cardiovascular surgery, thoracic surgery, head and neck surgery, pelvic surgery and skin and subcutaneous tissue procedure.
It is generally accepted to use multilayered fabrics in connection with medical procedures. For example, multilayered fabrics are used as all purpose pads, wound dressings, surgical meshes, including hernia repair meshes, adhesion prevention meshes and tissue reinforcement meshes, defect closure devices, and hemostats.
U.S. Pat. No. 5,593,441 to Lichtenstein et al describes a composite prosthesis preferably having a sheet of polypropylene mesh that allows tissue in-growth, such as Marlex® mesh. This reference discloses that other surgical materials that are suitable for tissue reinforcement and defect closure may be utilized, including absorbable meshes such as polyglactin 910 (Vicryl®) mesh. The composite prosthesis of Lichtenstein et al also has an adhesion barrier, preferably a sheet of silicone elastomer. This reference generally suggests that that an oxidized regenerated cellulose such as Interceed® (TC7) absorbable adhesion barrier (commercially available from Ethicon, Inc., in Somerville, N.J.) may be used as the adhesion barrier to produce a composite prosthesis having short term effectiveness.
U.S. Pat. No. 5,686,090 to Schilder et al describes the use of a fleece in combination with a nonabsorbable or absorbable film to prevent mis-growths to adjacent tissue and to reduce adhesions. Schilder et al generally discloses that polypropylene, polyester, polyglactin, polydioxanone or poliglecaprone 25 may be used as the fleece material or the film material. Published U.S. Patent Application 2006/00084930, to Dhanaraj et al, describes a reinforced absorbable multilayered fabric that can be used in medical devices specifically for tissue engineering applications. The matrix comprises first preparing a repair site for implantation, and then disposing the reinforced absorbable multilayered fabric at site. The first absorbable nonwoven fabric comprises fibers comprising aliphatic polyester polymers, copolymers or blends thereof; while the second absorbable woven or knitted fabric comprises oxidized regenerated cellulose fibers. Although the cells are seeded onto the 9010 PLGA component of the matrix before it migrates through the nonwoven matrix and comes in contact with the ORC component. The ORC component typically breaks down in about two weeks and the degradation components create an acidic environment that may not be conducive to cell proliferation or viability. The present invention addresses that by having a totally absorbable synthetic matrix that does not create such environment that is not conducive for cell viability
U.S. Pat. No. 4,626,253 to Broadnax et al, describes a device that relates to a surgical hemostat (SURGICEL) for control of bleeding, and more particularly, to a knitted fabric of oxidized cellulose having superior handling and hemostatic properties. U.S. Pat. No. 7,666,803 to Shetty et al. describes the method of making or reinforced absorbable multilayered fabric that can be used as a hemostat. The matrix comprises first preparing a repair site for implantation, and then disposing the reinforced absorbable multilayered fabric at site. The first absorbable nonwoven fabric comprises fibers comprising aliphatic polyester polymers, copolymers or blends thereof; while the second absorbable woven or knitted fabric comprises oxidized regenerated cellulose fibers. The method also describes the appropriate densities and thickness that can be used to make the matrix in that particular invention. However in certain applications where both the hemostasis function and an increased mechanical property is required over a longer period of time, the matrix mentioned will not satisfy both the requirements primarily due to its weaker mechanical properties.
Published U.S. patent application 2008/0033333 to MacPhee et al describes the use of DEXON (polyglycolic acid woven matrix) as a backing material for fibrinogen and thrombin, U.S. Pat. No. 6,762,336 describes the use of glycolic acid or lactic acid based polymers or copolymers (VICRYL) as one layer to support the sandwich layers of fibrinogen and thrombin. Similarly, fibrin sealant pads that were described as developed by the American Red Cross are described in various articles, such, the The Potential Utility of Fibrin Sealant Dressing in Repairing of Vascular Injury in Swine, Bijan Kheirabadi et al., Journal of Trauma Injury, Infection and Critical Care, January 2007, pp. 94-103 and Comparison of 10 Different Hemostatic Dressings in an Aortic Injury, Jill Sondeen et al., Journal of Trauma, Injury, Infection and Critical Care, February 2003, pp. 280-285.